Aspirin : Therapeutic uses, Dosage & Side Effects
Aspirin is a acetylsalicylic acid (ASA) & non-selective COX inhibitor (traditional NSAID) that irreversibly acetylates (and, thus, inactivates) cyclooxygenase, used to treat pain, and reduce fever or inflammation. It is sometimes used to treat or prevent heart attacks, strokes, and chest pain (angina).
Dose : 81 mg- 1 g
Route : Oral
Plasma Half-life : Dose-dependent; 2–3 hours for low doses, 15–30 hours for large doses
Duration of action : ?
Bioavailability : 80–100%
Chemical formula : C9H8O4
IUPAC name : 2-(acetyloxy)benzoic acid
Trade name : Bayer, Bufferin, Ecotrin, Ecospirin, Disprin, Loprin, Biospirin, Arthritis Pain, Ascriptin, Aspir 81, Aspir-Low, Durlaza, Ecpirin, Fasprin, Halfprin, Miniprin
Therapeutic uses : Aspirin has following usage :
- Used as Anti-inflammatory agent in the treatment of osteoarthritis, gout, and Reumatoid arthritis (RA).
- Used as Analgesic agent treat common conditions (for example, headache like mild migraine, arthralgia,joint pain, myalgia, backache, pulled muscle, toothache, neuralgias and dysmenorrhea) requiring analgesia.
- Used as Antipyretic agent to treat fever.
- Can be used to treat Acute rheumatic fever.
- Combinations of opioids and NSAIDs may be effective in treating pain caused by malignancy.
- Used to reduce risk of cardiovascular events since it reduce TXA2-mediated vasoconstriction and platelet aggregation. It can be used in Postmyocardial infarction and poststroke patients to lowers the incidence of reinfarction. It reduces the risk of recurrent cardiovascular events and/or death in patients with previous MI or unstable angina pectoris. It reduce the risk of recurring transient ischemic attacks (TIAs) and stroke or death in those who have had a prior TIA or stroke. It reduce the risk of cardiovascular events or death in high-risk patients such as those with chronic stable angina or diabetes.
- It can also be used in Pregnancv-induced hypertension and pre-eclampsia, Patent ductus arteriosus, Familial colonic polyposis, Prevention of colon cancer, To prevent flushing attending nicotinic acid ingestion, which is due to PGD1 release in the skin .
Side effects : The most common adverse effects of NSAIDs are GI related. Aspirin may cause following Side effects :
- Epigastric distress,
- Increased occult blood loss in stools,
- Gastric mucosal damage,
- Peptic ulceration,
- Increased risk of bleeding (antiplatelet effect),
- Increase the risk of exacerbations of asthma,
- CNS effects sucvh as headache, tinnitus, and dizziness,
- Hypersensitivity and idiosyncrasy.
Acute salicylate poisoning is more common in children. Serious toxicity is seen at serum salicylate levels > 50 mg/ dl. Manifestations are Vomiting, dehydration, electrolyte imbalance, acidotic breathing, hyper / hypoglycaemia, petechial haemorrhages, restlessness, delirium, hallucinations, hyperpyrexia, convulsions, coma and death due to respiratory failure + cardiovascular collapse.
- Aspirin is contraindicated in patients who are sensitive to it and in peptic ulcer, bleeding tendencies, in children suffering from chicken pox or influenza.
- Due to risk of Reye’s syndrome pediatric formulations of aspirin are prohibited in India and the UK.
- In chronic liver disease: cases of hepatic necrosis have been reported.
- It should be avoided in diabetics, in those with low cardiac reserve or frank CHF and in juvenile rheumatoid arthritis.
- Aspirin should be stopped 1 week before elective surgery.
- Given during pregnancy it may be responsible for low birth weight babies. Delayed or prolonged labour, greater postpartum blood loss and premature closure of ductus arteriosus are possible if aspirin is taken at or near term.
- It should be avoided by breastfeeding mothers.
- Avoid high doses in G-6-PD deficient individuals-haemolysis can occur.
For detailed query or in case of uncertainty, Always consult your doctor or pharmacist.